An shielded optical fiber assembly comprised of means for converting electrical energy to optical energy, transferring such optical energy to a desired site, and then converting such optical energy back into electrical energy.
In U.S. Pat. No. 5,549,642 of Xiaoyi Min et al., which is assigned to Medtronic, Inc., there is disclosed and claimed xe2x80x9cAn apparatus for delivering cardioversion pulses to the atrium of a patient""s heart, comprising: means for sensing atrial tachyarrhythmia; a first electrode means for location in the coronary sinus of said patient""s heart; a second electrode means for location in the right ventricle of said patient""s heart; a third electrode means for location in the right atrium/superior vena cava portion of said patient""s heart; means for coupling said first electrode means to said second electrode means; an implantable high voltage pulse generator having a housing and coupled to said first, second and third electrode means and including means for delivering a cardioversion pulse between said first and second electrode means while coupled to one another and said third electrode means, in response to a sensed occurrence of atrial tachyarrhythmia.xe2x80x9d
The device of U.S. Pat. No. 5,549,642 is comprised of pacemaker/cardioverter/defillibrator 110 and, connected thereto, lead bodies 115/116, each of which is comprised of a conductive material (such as, e.g., copper). These lead bodies, whose primary function is to conduct electricity to an implanted device near or in a heart, also act both as receiving and transmitting antennas. Consequently, when a patient in whom these leads 115/116 have been implanted is subjected to nuclear magnetic resonance imaging diagnosis, unwanted electromagnetic radiation will be absorbed, transformed, and/or emitted by leads 115/116.
U.S. Pat. No. 5,713,924 of Xiaoyi Min et al, which is also assigned to Medtronic, Inc., discloses and claims: xe2x80x9cA device for providing a combined defibrillation therapy, comprising: pacing electrode means for delivering pacing energy pulse bursts to a first chamber of a patient""s heart; defibrillation electrode means for delivering high energy pulses to said first chamber of said heart; means for detecting fibrillation in said first chamber of said heart; means for triggering delivery of said combined defibrillation therapy in response to detection of fibrillation in said first chamber of said heart; pacing pulse generator means responsive to said triggering means for delivering pacing energy pulse bursts having a frequency of 20 hz or greater to said pacing electrode means; defibrillation pulse generator means responsive to said triggering means for generating said high energy pulses for delivering a high energy pulse to said defibrillation electrode means in conjunction with each delivery of a said pulse burst to said pacing electrode means.xe2x80x9d
The device of U.S. Pat. No. 5,713,924 also contains conductive RA/SVC lead 140, and CS lead 130, each of which is comprised of conductive material, each of which serves to convey electricity to a device within or near a heart, and each of which also has the undesired property of acting as an emitting and/or receiving antenna;
In order to avoid the problem of using leads with conductive materials, some have proposed the use of an optical fiber delivering optical energy which can be converted into electrical energy prior to being delivered to an implanted device. However, the devices which have been proposed utilizing such optical fiber generally have poor power conversion efficiency.
It is an object of this invention to provide an optical fiber assembly that will convert electrical energy to optical energy, transfer such optical energy to a desired site, and then convert such optical energy back into electrical energy, all at a relatively high overall conversion efficiency.
In accordance with this invention, there is provided a shielded assembly comprised of a means for generating an electric current, means for converting said electric current to optical energy, means for converting said optical energy to electrical energy, and means for delivering electrical energy to a load, wherein said means for delivering said electrical energy to a load is coated with a composition comprised of at least about 50 weight percent of nanomagnetic material.